Syringe



Patented Apr.. 22,k 1924.

l UNITED STATES GEORGE T. PEARSONS, OF NEX YORK, N. Y.

SYRINGE.

Application filed April 21, 1920. Seria! No. 375,463.

To all whom t may concern: n Be it known that I, GEORGE T. PnnRsoNs, ya citizen of' the United States, and a `resident of the borough of Manhattan, in the city,` county, and State or New York, have invented' certain new and useful Improvements in. Syringes, oi' which the following is a specification. y

This invention relates to apparatus of the syringe type iny which liquid is discharged from a reservoir by the actuation of a reciprocable piston cylinder pump in which the liquid isdrawn from the reservoir upon each inward and outward movement of. the piston. v c

It is thel principal object' of the invention to provide apparatus of this character in which vthe liquid as it is drawn from the `reservoir upon eachv inward and outward movement of the piston lis discharged into fa casing or chamber with which the outlet of the-reservoir is in communication, said chamber or'casing containingair which is com-pressed to place the liquid as it is discharged thereinto by the pumping mechanismunder pressure yand serve to eject the liquid from said chamber. f

In 'the/drawing accompanying and ltorming a part of this specification l have shown in sectional side elevation apparatus embodying my invention. f

In the embod'ment. of my invention shown in the drawing there is. provided a reservoir comprising a cylindrical body portion 2 having -a closure at one end to constitute the bottom and arranged to support the reservoir in vertical position, the other end having a closure t arranged with a ller opening closed by a removable plug or cap 5, said end also being provided with an air inlet valve 6 operable to permit of the entrance of air into said reservoir to displace the liquid as it is discharged from the reservoir.

The pump mechanism comprises a cylinder 7 extending from the top to the bottom of the reservoir, the piston chamber proper being formed by partitions 8, 9 lo'- cated substantially equidistantly from the top and bottom of the reservoir, the p-ortion of the cylinder above the partition 8 being connected to the reservoir by ports or openings 10, and the portion below the partition 9 by a perforation or opening 11. A piston 12 provided with suitable packing is reciprocable in the cylinder or piston chamber and operates to separate the piston chamber into two compartments, one at the forward end and the other at the rear end of ythe piston. The pistony is carried by a rod 13 passing through a stuiing bio-X 14 in the partition 8 and a stuffing -box 15 in the i top ot the reservoir and having an operating handle at the outer end to manipulate the piston. The compartment at the forward 'end 'of the piston is connected to the reservoir by a pipe 16 extendingfrom the lower' end of the piston chamber to the bottom of the reservoir and having a valve 17 opening inward to and closing outward from the' piston chamber. The: compartment of the piston chamber at the rear end v n of the piston is connectedv to the reservoir by a pipe 18 extending tio-adjacent the bottom ot the reservoir and also being provided with anA inwardly opening and outwardlyy closing valve 19.

y lhe liquid, is drawn alternately. to the compartments of the piston chamber at opposite sides of the piston during the reciprocation ot the piston through pipes 16,18 and is alternately discharged from said compartments through a pipe 2O connected to a port leading from the compartment at the rear of the piston, saidy pipe having a check valve 21 closinginto and opening outward from the piston adjacent the connection of said latter pipev with the air chamber C. The discharge outlet of the reservoir leads from the chamber C inthe form of a tube 25 extending from the top of the reservoir to a point below the connection of the pipe 22 with. the chamber C, and has a flexible hose 26 connected thereto provided with a discharge nozzle.

In operation as the piston is reciprocated liquid is drawn from the reservoir alternately to the compartments of the piston chamber at opposite sides of the piston and from the reservoir` y alternately discharged from said compartments into the air chamber C compressing the air therein and such compressed air operating to eject the liquid from the air chamber through the pipe 25. Y

Having thus described my invention, I claim: Y

l. The combination of a reservoir; a chamber in the reservoir connected at opposite ends with the reservoir; a piston in said chamber; an air compression chamber in the reservoir extending between opposite ends thereof; an outlet tube :tor the liquid in the reservoir engaging in said air chambei' having an outlet from one end to said chamber and the'inlet end of the tube eX- tending to adjacent the opposite end of the chamber; and means to connect the opposite ends of the piston ,chamber adjacent the inlet end of the outlet tube thereinrwith the air chamber for the purpose specified.

2. Thecombination with a reservoir to Vcontain liquid, of an air chamber extending from end to'end of the reservoir; an outlet tube for the reservo-irengaging in said air chamber havingan outlet from one end of the chamber andthe inlet adjacent the opposite end of the chamber: a cylinder in the reservoir; ports in the cylinder adjacent opposite ends connected to the reservoir adjacent ,one end thereof; a Valve for each of said ports opening into and closing out- Ward from the cylinder to controlk said ports; ports. inthe cylinder adjacent opposite ends connected to the air chamber adjacent the inlet end of the outlet tubel therein; a valve for each of said ports closing into and opening outward from the cylinder to control said outlet ports; and a piston to reciprocate in the cylinder for the purpose specied.

3. The combination with a reservoir Vto 4. The combination with a reservoir tocontain liquid, of an air compression chainber in the reservoir extending from the ltop to the bottom of the reservoir; an outlet tube for the reservoir extending from the top to adjacent the bottom of the air compression@- chamber; Aa cylinder in the reservoir in parallel relation to the air compression chamber; a piston to reciprocate in said cylinder and separating the cylinder into a'pair of chambers one at opposite sides ofthe piston; an inlet port to each of said cham-i.

bers from the reservoir; tubes connected to said inletrports extending to adjacent the bottom vof the reservoir; a suction Valve in each of said tubes; an outlet port from each* of said cylinder chambers at opposite ends of the piston; tubes connecting the outlets with the air chamber at a point above the inlet end of the outlet tube; and a Valve for' each of vsaid outlet tubes of the chambers- Signed at the city of New York, in the county of New York, and State of New York, this 16th day of April, 1920.

GEO. T. PEARSONS. 

